Budytes cinereocapilla, Savi.
593.-B. viridis, Gm. :- Jerdon's Birds of India, Vol. II, p. 222 ; Butler, Deccan; Stray Feathers, Vol. IX, p. 410; Motacilla cinereocapilla, Savi., Swinhoe and Barnes, Central India; Ibis, 1885, p. 127.
THE SLATY-HEADED FIELD WAGTAIL.
Length, 6.5 ; expanse, 9.5 ; wing, 3.13; tail, 2.75 ; tarsus, 0.8 ; bill at front, 0.45.
Bill black ; irides dusky-brown; legs black.
The usual plumage of adult birds in winter is olive-green above, with a white or occasionally yellow superciliary mark; beneath, the chin and throat whitish, the rest yellow, more or less pure; wings dusky, with two dull whitish-yellow cross bands, formed by the tips of the coverts, and the tertials broadly margined with yellowish; tail black, slightly margined with greenish, and the two outermost feathers on each side chiefly white.
At the spring moult, the whole cap, lores and ear-coverts change to a bluish ash-grey, with or without a white or yellow supercilium, which, however, is not always present, and disappears eventually by the change of color which takes place in the feathers themselves at a later period. The lower parts, too, become more pure and bright yellow; the chin is white, and the throat yellow, with its lateral border white.
A little later in the season, the lores and ear-coverts become darker by a change in the feathers themselves, and finally change to a deep black; and in full breeding plumage, the whole cap, lores, and ear-coverts, are deep black.
Young birds of the year are light brownish-grey, purer on the nape and rump; wings and tail dusky, the former with two whitish, cross bands; the tail darker than the wings, with the two outermost feathers on each side nearly white ; beneath white, sometimes with a yellowish tinge, and a few brown marks on the breast; a white supercilium always present.
The Slaty-headed Field Wagtail is common in the Deccan and in parts of Rajputana. Of course it only occurs in the cold season.